Opus Audio Encoder

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sarexpert

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I am looking to port the OPUS audio encoder to Teensy 4.0/4.1. My use is to take a i2S input and continuously stream the compressed data to another serial port for further processing and distribution.
I understand that some folks have ported the Decoder of the Opus library to Cortex M series processors. Have you heard of any projects for the Encoder?
1) Is there any guidance you would give to make this project more generally applicable? (IE making it a useful library)
2) There are several implementations of the OPUS codec. Is anyone familiar with the tradeoffs of each of the implementations and the choice with relation to to a processor and multithreading and an FPU like the M7
3) Is there an FPU library for the Teensyduino system, or should I use a different IDE? Teensyduino looks to have the capabilities for the rest of the project, such as the pre-shared key encryption and Icecast style ogg encapsulation.
4) I welcome any guidance. I am an old pascal and C programmer, so this will be a bit of a challenge, so any advise would be welcome.
5) Does anyone else have need for an OPUS encoder?
 
Encoding compressed audio is much slower than decoding, though the T4 has serious grunt,
its worth being aware this might be an issue.

What do you mean by an FPU library? libm?
 
I recall looking at Opus some time ago. It wanted 8 kHz sample rate back then. Almost everything we do is for 44.1 kHz.
 
The opus decoder is in my codecs lib... have not done much with it.
8khz could be done by downsampling from 48kHz easyly, with the CMSIS. From 44.1 it will be bit more complicated.
But.. didn't have it an inbuilt resampler? I recall something... but its too long ago.
 
Opus encoding sample rates are multiple s of 8 khz, people mostly use 8, 16,24, 32,48,96,128.192.. 44.1 would have to be resampled to be encoded. My application would be using 48 kHz sampling rate. For code size, I will probably break out the encoder sewparately.
 
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